Cartons formed of paperboard such as bleached kraft, white coated paper newsboard and similar materials are well known in the art and are widely used. While commonplace, such articles appear simple but such appearances are deceptive. Cartons are carefully designed and constructed to accomplish multiple tasks.
The primary function of the carton, of course, is to contain its contents. Frequently, cartons are fabricated so as to contain an inner pouch or liner typically to provide additional moisture protection, e.g., for R-T-E cereals or to provide siftproof sealing for fine or granular material, e.g., flour or cake mixes. While enabling a simplified design, the addition of a liner adds costs to the container and adds complexity to filling and fabrication steps of their manufacture.
The present invention is, however, directed towards linerless cartons but which nonetheless are useful for the siftproof packaging of granular materials especially such as Potato Buds.RTM. brand granulated dehydrated mashed potatoes Other granulated materials such as laundry detergent can also be suitably packaged by the present cartons. Thus, an important performance characteristic is to prevent leakage of the fine granules or dust from the container both when initially sealed and also upon reclosure. Typically, leakage problems are most severe at carton corners and especially the upper corners.
Another function very desirable in a carton is to be easily openable. However, the employment of features and materials to make the carton siftproof such as improved strengths of heat seal bonds often interfere with the ease of opening such packages by the consumer.
Still another function which is desirable in a carton for granular materials is to have a spout feature. A spout feature assists in the controlled dispensing of the contents. The two important aspects of a spout feature are first to have a controlled opening of the open face of the container and second to have guides to control the outward flow of the contents during dispensing.
It is further desirable to have a reclosure feature for the carton where it is desirable to reclose the carton after dispensing less than all its contents. Such a feature becomes more important with larger sized cartons.
Still another advantage of an improved carton is to be able to be fabricated from a single carton blank without the need for additional structures such as discrete dispensing spouts or reclosure/spout elements. Such simplicity of design offers improvements in cost savings.
As can be readily appreciated, improvements in one aspect or function of a carton can undesirably adversely affect other functions. Carton design often involves numerous trade-offs in benefits. Accordingly, there is a continuing need for new, improved and innovative carton designs providing multiple desirable features at reduced cost. Surprisingly, the present invention provides such improved cartons containing such features by a combination of selected cut lines, score lines, perforation lines and adhesive lines. It is surprising that such dramatic combinations of features and cost benefits can be provided by such simple manufacturing techniques.